1. Field of the Invention
The invention relates to a motor vehicle door lock with a lock mechanism, such as rotary latches and detent pawls, and with a central interlock drive which has a drive motor, a rotor that is driven in a rotating manner by the drive motor, preferably with the aid of a worm-gear transmission, and an actuating part which is arranged on the rotor and which can be brought into a release position, a locking position, and preferably, an anti-theft locking position, optionally also into a neutral position. More specifically, to such a door lock in which the locking mechanism has an inside opening lever, an outside opening lever and other levers as well as a central interlock lever that can be displaced by the actuating part.
2. Description of the Related Art
Motor vehicle door locks of the type in question are known in various embodiments. The motor vehicle door lock on which the invention is based (U.S. Pat. No. 5,240,296) has a central interlock drive with a drive motor and a rotor which is turned by the drive motor with the aid of a worm-gear transmission. An actuating part in the form of a projecting pin is located near the periphery of the rotor and thus rotates eccentrically. The actuating part can be brought with the aid of the rotor into a release position and a locking position as well as into an intervening neutral position.
The actuating part acts in combination with a central interlock lever of the lock mechanism, which is mounted to pivot about an axis that is parallel to the axis of rotation of the rotor and which has a T-shaped section with a base leg that is directed radially outward. The release position and the locking position of the actuating part are located in the cross-piece of the T-shaped section at approximately opposite ends areas thereof. The central interlock lever is thus swung back and forth around its pivot axis between the release position and the locking position by the actuating part. This swinging movement then acts on the other levers in the lock mechanism.
In the case of the above-explained, known motor vehicle door lock, after a locking process or release process, the actuating part normally occupies a neutral position that lies in the center between the locking position and the release position, in the cross-piece of the T-shaped section. In this neutral position, the swinging movement of the central interlock lever between the locking position and the release position is not impeded.
An anti-theft locking position can be achieved in the above-explained motor vehicle door lock in which the rotor moves the actuating part into the locking position and disconnects the drive motor there. The actuating part is now stationary while blocking the central interlock lever in the locking position, pulling on the inside locking lever, or on the inside opening lever that can also achieve the inside locking, cannot lead to a unlocking of the door lock.
In order that the lever gear of the lock mechanism, in this design in which the central interlock lever is blocked in the anti-theft locking position, is not damaged, a coupling spring can be arranged between the inside locking lever or the inside opening lever that achieves the inside locking, on the one hand, and the central interlock lever, on the other hand. This coupling spring normally entrains one lever in the case of mechanical actuation of the other lever, but in the case of blocking the other lever, it allows a movement of one lever against the spring force.
If, in the case of the above-explained motor vehicle door lock, the central interlock drive is permanently blocked in the anti-theft locking position or in any other intermediate position for whatever reason, the central interlock lever cannot be moved and it is correspondingly permanently blocked. A repair in the workshop is unavoidable. Worse yet, without special additional measures, an emergency release or emergency unlocking of the motor vehicle door lock cannot be achieved via the outside locking lever to be actuated by the door lock. Rather, an additional chain of action of forces from the outside locking lever directly to the detent pawl of the motor vehicle door lock must be provided.